Is it OK for little boys to dress up as girls?

A mother’s decision to allow her 5-year-old son to dress up as a female cartoon character for a preschool Halloween party has lit up the blogosphere. Her account of the negative reaction and disapproving looks she received from some parents so far has generated more than 3 million page views and tens of thousands of comments from across the globe.

The mom, Sarah (she asked that her last name not be revealed), told TODAY’s Meredith Vieira on Monday: “I really thought it was Halloween, that you get to dress up as what you are not. It’s a fun holiday.

“No child said a word to him, not in any sort of negative way,” she added. “It was the parents, just a few.”

Sarah kept her cool, for the sake of her son, whom she calls Boo. She didn’t make a big scene at the school, but thought about it a lot before she sat down at her computer and began writing a post for her blog, Nerdy Apple Bottom, under the provocative headline “My son is gay.” “It weighed heavily on me,” she said.

In the blog, Sarah asked: So what if Boo wanted to go to the party dressed as “Daphne” from the Scooby-Doo animated series? Whatever the reason for it, her son deserved his mother’s love and support, she felt.

Sarah got it exactly right, said another guest in the TODAY segment: Cheryl Kilodavis, whose own son, Dyson, began wearing sparkly and colorful dresses in preschool and still does at age 5. Kilodavis said that while it is important to understand why children cross-dress, it is more important that they are happy and know that they are loved however they dress.

“The discussion is, what is going to make this more accepted?” Kilodavis told Vieira. “We have children who are expressing themselves differently, and we need to get to a place of acceptance.”

Kilodavis self-published a book on what her son and her family went through while trying to understand his choices. Titled “My Princess Boy,” the book became popular via the Internet.

Kilodavis told Vieira that she now regrets some of her early reactions to Dyson’s decision to wear dresses: “Not proud mom moments,” she called them.

No cause for alarmExperts say it is not unusual for boys under the age of 5 to dress up in clothing or costumes typically associated with girls. (Who hasn’t seen a little boy dress up in his mom’s high heels and pearls?)

Girls can want to dress up as boys as well. For example, in the August issue of Vanity Fair, Angelina Jolie said that Shiloh, her 4-year-old daughter with Brad Pitt, “likes to dress as a boy. She wants to be a boy. So we had to cut her hair. She likes to wear boys’ everything.”

But around the age of 5, children become aware of the differences between the genders and for most, the desire to cross-dress goes away. Parents should not become alarmed if a child still plays dress-up past age 5; they should, however, try to understand the reasons for it.

“It’s always difficult to be different. When children are different, it makes everyone anxious,” Dr. Harold Koplewicz, president of the Child Mind Institute, told Vieira on TODAY. “We have to make sure our children feel loved and feel supported.

“The important thing is that they still like themselves and their bodies,” he added.

When Kilodavis sought professional advice about Dyson’s interest in dressing up as a girl, psychologists and psychiatrists did various assessments for what they thought could be gender confusion. Whether or not Dyson loses interest in cross-dressing as he grows older, Kilodavis said she’ll love Dyson in any event.

“The doctor said: ‘The verdict is, you have a healthy and happy little boy who just likes to dress up,’ ” Kilodavis said.

In the blogosphere, there has been approval for Sarah’s position as well. Most of the comments on her blog about Boo’s “Daphne” costume have been positive.

“I applaud you for letting your child be unique, imaginative and free from the constraints of our closed society,” one poster wrote after Sarah’s appearance Monday on TODAY. “This is not a gender issue, this is not a gay or straight issue, this is a parenting issue and you have passed.”